/*
* Copyright (C) 2010, Google Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
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* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY
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*/
#ifndef AudioUtilities_h
#define AudioUtilities_h
#include "platform/PlatformExport.h"
namespace WebCore {
namespace AudioUtilities {
// Standard functions for converting to and from decibel values from linear.
PLATFORM_EXPORT float linearToDecibels(float);
PLATFORM_EXPORT float decibelsToLinear(float);
// timeConstant is the time it takes a first-order linear time-invariant system
// to reach the value 1 - 1/e (around 63.2%) given a step input response.
// discreteTimeConstantForSampleRate() will return the discrete time-constant for the specific sampleRate.
PLATFORM_EXPORT double discreteTimeConstantForSampleRate(double timeConstant, double sampleRate);
// Convert the time to a sample frame at the given sample rate.
PLATFORM_EXPORT size_t timeToSampleFrame(double time, double sampleRate);
} // AudioUtilites
} // WebCore
#endif // AudioUtilities_h